The present invention relates generally to the transmission of information in a communications network. More particularly, the invention relates to encapsulating large functional units as software components to be used in different operating environments.
A communications network, such as the Internet, can transmit pages of information to a user's computer for display by a software program called a “browser.” One example of such an information page is used in the World Wide Web (also called simply the “Web”), which transmits information pages over the Internet using hypertext markup language (HTML). The HTML data can include source codes that tell the browser how to display the page, including for example, the location and color of text and graphics. In general, a Web page can include combinations of text, graphics, sound video and small application software programs, such as “applets” written in the Java computer language developed by Sun Microsystems located in Palo Alto, Calif. and “ActiveX controls” developed by Microsoft Corporation located in Redmond, Wash. and written in a variety of programming languages including Microsoft's Visual C++ and Microsoft's Visual Basic programming system.
Many software programs, including these small application software programs are created using Object-Oriented Programming (OOP) techniques which involve the definition, creation, use and destruction of “objects.” Objects are self-sufficient software entities including data elements and routines, or functions, sometimes called methods, which are used to manipulate the data elements. The object's data and related functions are treated by the software as an entity and they can be created, used and deleted as if they were a unitary item. Together, the data and functions enable objects to model virtually any real-world entity in terms of its characteristics, which can be represented by the data elements, and its behavior, which can be represented by its data manipulation functions. In this way, objects can model concrete things like people and computers, and they can also model abstract concepts like numbers or geometrical designs.
Objects are defined by creating “classes” which are not per se objects themselves, but which act as templates that instruct a compiler how to construct an actual object. A class may, for example, specify the number and type of data variables and the steps involved in the functions which manipulate the data. An object is actually created in the program by means of a special function called a constructor which uses corresponding class definitions and additional information, such as arguments provided during object creation, to construct and initialize the object and its data members. Likewise objects are destroyed by a special function called a destructor. Objects are employed by using their data and invoking their functions to accomplish a task. In a simple example, a class could be defined as dogs having the characteristic of barking, running and panting. A collie would then be an object of the class dogs.
It is noteworthy to distinguish between an object and a class of objects. A class is a type definition or template used to create objects in programs. The objects created are merely each a single instance of the class of objects, which is just called a class. A class has no memory or behavior of its own except to serve as the blueprint from which objects can be created. As stated previously, an object is a self-sufficient component that includes both data and function. An object is of the same type as the class from which it has been derived. Objects are said to be instantations of their class and use memory for their data and functions, unlike the class template itself which does not.
Objects can represent physical things, such as airplanes in an air traffic control system, components in a stereo or television system, balance sheet and income statement elements in a fundamental analysis company business model, or stars in the simulated night sky on display at a planetarium. Objects can represent elements of the computer-user environment such as windows, scrollbars, sliders, menus or other graphical items. An object can represent a collection of data, such as a personnel file or a table of the latitudes and longitudes of cities, or an object can represent user-defined data types such as time, angles, and complex numbers, functions or points on the plane.
As the Web emerges as the primary medium for delivery of information and functional capabilities (i.e., application programs, etc.) to users, there arises a need to integrate large functional units, such as for example, large application programs created using Object-Oriented Programming (OOP) techniques, (i.e., Microsoft Word, Excel, CAD software programs, etc.) in a Web page to deliver to these users.
Large functional units have not been the focus of attention in the past because of processing considerations and bandwidth limitations. Conversely, the focus has been directed to delivering small functional units such as applets, ActiveX controls, etc. that perform specific tasks and produce small levels of functionality to the Web.
Thus, the present invention provides for encapsulating large functional units which can be operable in both the Web and the desktop environments.